/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2006 Refractions Research Inc.
 *
 * This is free software; you can redistribute and/or modify it under
 * the terms of the GNU Lesser General Licence as published
 * by the Free Software Foundation.
 * See the COPYING file for more information.
 *
 **********************************************************************
 *
 * Last port: noding/snapround/HotPixel.java r320 (JTS-1.12)
 *
 **********************************************************************/

#include <geos/noding/snapround/HotPixel.h>
#include <geos/noding/NodedSegmentString.h>
#include <geos/algorithm/LineIntersector.h>
#include <geos/geom/Coordinate.h>

#ifndef GEOS_INLINE
# include "geos/noding/snapround/HotPixel.inl"
#endif

#include <algorithm> // for std::min and std::max
#include <cassert>
#include <memory>

using namespace std;
using namespace geos::algorithm;
using namespace geos::geom;

namespace geos {
namespace noding { // geos.noding
namespace snapround { // geos.noding.snapround

HotPixel::HotPixel(const Coordinate& newPt, double newScaleFactor,
                   LineIntersector& newLi)
    :
    li(newLi),
    pt(newPt),
    originalPt(newPt),
    scaleFactor(newScaleFactor)
{
    if(scaleFactor != 1.0) {
        assert(scaleFactor != 0);   // or should it be an IllegalArgumentException ?
        pt.x = scale(pt.x);
        pt.y = scale(pt.y);
    }
    initCorners(pt);
}

const Envelope&
HotPixel::getSafeEnvelope() const
{
    static const double SAFE_ENV_EXPANSION_FACTOR = 0.75;

    if(safeEnv.get() == nullptr) {
        double safeTolerance = SAFE_ENV_EXPANSION_FACTOR / scaleFactor;
        safeEnv = unique_ptr<Envelope>(new Envelope(originalPt.x - safeTolerance,
                                       originalPt.x + safeTolerance,
                                       originalPt.y - safeTolerance,
                                       originalPt.y + safeTolerance
                                                   ));
    }
    return *safeEnv;
}

/*private*/
void
HotPixel::initCorners(const Coordinate& p_pt)
{
    double tolerance = 0.5;
    minx = p_pt.x - tolerance;
    maxx = p_pt.x + tolerance;
    miny = p_pt.y - tolerance;
    maxy = p_pt.y + tolerance;

    corner.resize(4);
    corner[0] = Coordinate(maxx, maxy);
    corner[1] = Coordinate(minx, maxy);
    corner[2] = Coordinate(minx, miny);
    corner[3] = Coordinate(maxx, miny);
}

bool
HotPixel::intersects(const Coordinate& p0,
                     const Coordinate& p1) const
{
    if(scaleFactor == 1.0) {
        return intersectsScaled(p0, p1);
    }

    copyScaled(p0, p0Scaled);
    copyScaled(p1, p1Scaled);

    return intersectsScaled(p0Scaled, p1Scaled);
}

/* private */
bool
HotPixel::intersectsScaled(const Coordinate& p0,
                           const Coordinate& p1) const
{

    double const segMinx = std::min(p0.x, p1.x);
    double const segMaxx = std::max(p0.x, p1.x);
    double const segMiny = std::min(p0.y, p1.y);
    double const segMaxy = std::max(p0.y, p1.y);

    bool isOutsidePixelEnv =  maxx < segMinx
                              || minx > segMaxx
                              || maxy < segMiny
                              || miny > segMaxy;

    if(isOutsidePixelEnv) {
        return false;
    }

    bool p_intersects = intersectsToleranceSquare(p0, p1);

    // Found bad envelope test
    assert(!(isOutsidePixelEnv && p_intersects));

    return p_intersects;
}

/*private*/
bool
HotPixel::intersectsToleranceSquare(const Coordinate& p0,
                                    const Coordinate& p1) const
{
    bool intersectsLeft = false;
    bool intersectsBottom = false;

    li.computeIntersection(p0, p1, corner[0], corner[1]);
    if(li.isProper()) {
        return true;
    }

    li.computeIntersection(p0, p1, corner[1], corner[2]);
    if(li.isProper()) {
        return true;
    }
    if(li.hasIntersection()) {
        intersectsLeft = true;
    }

    li.computeIntersection(p0, p1, corner[2], corner[3]);
    if(li.isProper()) {
        return true;
    }
    if(li.hasIntersection()) {
        intersectsBottom = true;
    }

    li.computeIntersection(p0, p1, corner[3], corner[0]);
    if(li.isProper()) {
        return true;
    }

    if(intersectsLeft && intersectsBottom) {
        return true;
    }

    if(p0.equals2D(pt)) {
        return true;
    }
    if(p1.equals2D(pt)) {
        return true;
    }

    return false;
}

/*private*/
bool
HotPixel::intersectsPixelClosure(const Coordinate& p0,
                                 const Coordinate& p1)
{
    li.computeIntersection(p0, p1, corner[0], corner[1]);
    if(li.hasIntersection()) {
        return true;
    }
    li.computeIntersection(p0, p1, corner[1], corner[2]);
    if(li.hasIntersection()) {
        return true;
    }
    li.computeIntersection(p0, p1, corner[2], corner[3]);
    if(li.hasIntersection()) {
        return true;
    }
    li.computeIntersection(p0, p1, corner[3], corner[0]);
    if(li.hasIntersection()) {
        return true;
    }

    return false;
}

bool
HotPixel::addSnappedNode(NodedSegmentString& segStr, size_t segIndex)
{
    const Coordinate& p0 = segStr.getCoordinate(segIndex);
    const Coordinate& p1 = segStr.getCoordinate(segIndex + 1);

    if(intersects(p0, p1)) {
        //cout << "snapped: " <<  snapPt << endl;
        segStr.addIntersection(getCoordinate(), segIndex);
        return true;
    }
    return false;
}


} // namespace geos.noding.snapround
} // namespace geos.noding
} // namespace geos
